Flavoring with mixture of 2,5-dimethyl-3-acetyl-furan and 3,5-di-(2-methylpropyl)-1,2,4-trithiolane

ABSTRACT

Mixtures of 3,5-Di-(2-Methylpropyl)-1,2,4-Trithiolane having the formula: ##STR1## and its &#34;cis&#34; and &#34;trans&#34; isomers represented by the structures: ##STR2## together with one or more 3-Acetyl-2,5-Dialkyl Furan or Thiophene compounds having the generic formula: ##STR3## wherein X is sulfur or oxygen and R and R 1  is lower alkyl of 1 to 5 carbon atoms are described as being useful in augmenting or enhancing the organoleptic properties (taste and aroma) of foodstuffs.

This application is a Continuation-in-Part of application for UnitedStates Letters Patent Ser. No. 963,176, filed on Nov. 24, 1978.

BACKGROUND OF THE INVENTION

The present invention relates to novel uses in foodstuffs and infoodstuff flavors of mixtures of3,5-di(2-methylpropyl)-1,2,4-trithiolane or cis or trans isomers thereofhaving the structures: ##STR4## with 3-acetyl-2,5-dialkyl furans orthiophenes having the formula ##STR5## wherein X is sulfur or oxygen andR and R₁ are lower alkyl of 1 to 5 carbon atoms.

Artificial flavoring agents for foodstuffs have received increasingattention in recent years. In many areas, such food flavoring agents arepreferred over natural flavoring agents at least in part because of theuniform flavor that may be so obtained. For example, natural foodflavoring agents such as extracts, essences, concentrates and the likeare often subject to wide variation due to changes in the quality, typeand treatment of the raw materials. Such variation can be reflected inthe end product and results in unreliable flavor characteristics anduncertainty as to consumer acceptance and cost. Additionally, thepresence of the natural product in the ultimate food may be undesirablebecause of increased tendency to spoil. This is particularly troublesomein convenience and snack food usage where such products as dips, soups,chips, prepared dinners, canned foods, sauces, gravies and the like areapt to be stored by the consumer for some time prior to use.

The fundamental problem in preparing artificial flavoring agents is thatof achieving as nearly as possible a true flavor reproduction. Thisgenerally proves to be a difficult task since the mechanism for flavordevelopment in many foods is not understood. This is notable in productshaving roasted and smoked flavor characteristics, for example, roastedalmond, roasted pork and smoked sesame flavor characteristics.

Reproduction of roasted, crisp bacon and pork rind flavors and aromashave been the subject of a long and continuing search by those engagedin the production of foodstuffs. The severe storage of foods, especiallyprotein foods, in many parts of the world, have given rise to the needfor utilizing non-meat sources of proteins and making such proteins aspalatable and as meat-like as possible. Hence, materials which willclosely simulate or exactly reproduce the flavor and aroma of roastedpork products are required.

Moreover, there are a great many meat containing or meat based foodspresently distributed in a preserved form. Examples of these arecondensed soups, dry-soup mixes, dry meat, freezedried or lyophilizedmeats, packaged gravies and the like. While the products contain meat ormeat extracts, the fragrance, taste and other organoleptic factors areoften impaired by the processing operation and it is desirable tosupplement or enhance the flavors of these preserved foods withversatile materials which have either roasted pork or crisp bacon-likeor pork rind-like or "roasted" aroma and taste nuances.

In U.S. Pat. No. 3,863,013, it is disclosed that five or six numberedheterocyclo compounds having two sulfur atoms in the ring are useful toalter the flavor or aroma of foodstuffs. The di-thioheterocycliccompounds disclosed as suitable according to U.S. Pat. No. 3,863,013 arerepresented by the following formulae: ##STR6## and each of R₁ to R₄ ishydrogen or a lower alkyl radical of one to three carbon atoms. Most ofthese compounds are disclosed at column 2 and 3 of U.S. Pat. No.3,863,013 to have beef, garlic, vegetable and onion-type aromas andtastes, thusly:

"1,3-Dithiolane having the structure ##STR7## is described in Meadow, J.R. et al., J.A.C.S., Vol. 56, p. 2177 (1934) and U.S. Pat. No.2,690,988. It has a sweet, sulfury character, which in high levelsbecomes reminiscent of degrading onions. It is useful for its sulfurnotes in chocolate and coffee and roasted garlic notes found in stews,jellied veal dish and gravies. Taste threshold level is 2 parts perbillion (2 ppb).

2-Methyl-1,3-dithiolane having the structure ##STR8## is described in J.Chem.Soc., B, (1970), p. 404 at p. 407 and U.S. Pat. No. 2,690,988. Ithas a cooked, roasted onion character. The background notes are suitablefor stewed vegetable and vegetable protein hydrolyzate type flavors. Itstaste threshold value is 20 ppb.

3,5-Dimethyl-1,2-dithiolane having the formula ##STR9## is described inSchotte, L., Arkiv. Kemi., Vol. 9, p. 441 (1956). It has a cooked onionnote developing into a cooked vegetable nutty note. Its taste thresholdvalue is 10 ppb.

3-Methyl-1,2-dithiolane having the formula ##STR10## It has an onionymetallic taste with cooked beef or braised and vegetable nuances. It issuitable for stewed vegetable and braised beef flavors. Taste thresholdlevel is 2 ppb.

2,4-Dimethyl-1,3-dithiolane having the structure ##STR11## is describedin Leggeter B. E. et al. in Can. J. Chem., Vol. 41, No. 10, p. 2671(1963). It has an onion-like taste with slight metallic background notesand is suitable for stewed vegetable flavors. Its taste threshold valueis 20 ppb.

4-Methyl-1,3-dithiolane having the structure ##STR12## is generallydescribed in U.S. Pat. No. 2,690,988. It has an oniony, rootvegetable-like taste and is useful for stewed vegetable or braised beeftype flavors. Its taste threshold value is 50 ppb.

1,2-Dithiane(ortho-dithiane) having the formula ##STR13## is describedin Schoberl, A. Et al., Ann., Vol. 614, p. 66 (1958). It has a garliccharacter with slight metallic nuance and is suitable for stewedvegetable and horseradish flavors. Its taste threshold value is 2 ppb.

1,3-Dithiane(m-dithiane) having the formula ##STR14## and has beendescribed by Meadow & Read in J.A.C.S., Vol. 56, p. 2177 (1934). It hasan onion, garlic-like taste with a metallic by-note and is suitable formeat alium flavors. Its taste threshold value is 50 ppb.

1,4-Dithiane) having the formula ##STR15## has been described in J.Chem. Soc., B, (1970), p. 404 at 407. It has an onion-like orgarlic-like character and is useful for stewed vegetable type flavors.Its taste threshold value is 50 ppb.

2-Methyl-1,3-dithiane having the formula ##STR16## has been described byAutenreith, W. et al in Ber., 32, p. 1375 (1899). It has an onion-likecharacter with metallic notes and is suitable for vegetable typeflavors. Its taste threshold value is 20 ppb.

2,4-Dimethyl-1,3-dithiane having the formula ##STR17## is described byEliel et al., in J.A.C.S. Vol. 91, No. 10, p. 2703 (1969). It has anallium-onion like character with slight metallic notes and is suitablefor onion flavors. Its taste threshold value is 5 ppb.

4-Methyl-1,3-dithiane having the formula ##STR18## It has an onion,garlic and tomato like character and is suitable for stewed meats,gravy, tomato and onion flavors. It has a taste threshold level of 50ppb.

2,4,6-Trimethyl-1,3-dithiane having the formula ##STR19## has beendescribed by Eliel et al., J.A.C.S., 91, No. 10, p. 2703 (1969). It hasa root vegetable-like character and is suitable for stewed vegetable orpotato flavors. Its taste threshold is 10 ppb." Tetra and penta thiolanecompounds are also disclosed for use in flavoring compositions forfoodstuffs by U.S. Pat. Nos. 3,503,758 and 3,488,362. Thus, for example,in U.S. Pat. No. 3,503,758 compounds having the generic structure##STR20## wherein X may be

    --CH.sub.2 --S--,--CH.sub.2 --,

    --CH.sub.2 --S--CH.sub.2 --

or

    --S--CH.sub.2 --S--

Specifically, the compounds: 1,2,3,5,6-pentathiepane (lenthionine);1,2,3,5-tetrathiane; 1,2,4,6-tetrathiepane, and 1,2,4,5-tetrathianeindicated to be useful in, for example, enhancing pork and beef flavors.

A paper in Tetrahedron, Vol. 28, pages 3489-3500 (1972) entitled:"Synthesis of 3,5-Dialkyl-1,2,4-Trithiolanes/Assignment of Configurationand Conformational Analysis by PMR" by Tjan, Haakman, Teunis and Peer ofthe Unilever Research Duiven of the Netherlands discloses the synthesisof 3,5-dialkyl-1,2,4-trithiolanes of the structure: ##STR21## wherein Ris disclosed to be either of methyl, ethyl, isopropyl or t-butyl. It isalso disclosed by Tjan et al that such materials may be synthesizedaccording to the technique of Asinger et al, Liebigs Ann. Chem. 627, 195(1959).

Brinkman et al, J. Agr. Food Chem. 20,177 (1972) during theirinvestigations into components contributing to beef flavor isolated frombeef broth two volatile isomers which are tentatively identified as3,5-dimethyl-1,2,4-trithiolanes. In addition, Chang et al Chem. Ind.(London) 1639 (1968) isolated two isomeric3,5-dimethyl-1,2,4-trithiolanes from boiled beef and suggested that theisomers were in "cis" and "trans" forms but made no structuralassignment. In paragraph 2 of the Tjan et al article, it was stated:

". . . It was necessary to synthesize compound I(3,5-dimethyl-1,2,4-trithiolane, and in view of the promisingproperties; of the compounds as flavoring agents, we investigated a moregeneral synthesis for 3,5-dialkyl-1,2,4-trithiolanes . . ."

Canadian Pat. No. 623,330 discloses and claims 1,2,4-trithiolanes havingthe formula: ##STR22## wherein R₁ is alkyl or hydrogen and R₂ is alkyl.Specifically disclosed are 3,5-di-n-propyl-1,2,4-trithiolane and3,5-diethyl-1,2,4-trithiolane.

However, nothing in the prior art including subject matter mentioned inthe Tjan et al article or in Canadian Pat. No. 623,330 suggests thesynthesis and flavor use and flavor characteristics of the3,5-di-(2-methylpropyl)-1,2,4-trithiolane or of its cis or trans isomersof our invention.

In addition, U.S. Pat. No. 3,885,051 issued on May 20, 1975 discloses3-acetyl-2,5-dialkyl furan or thiophene compounds having the formula##STR23## wherein X is sulfur or oxygen and R and R₁ is lower alkyl of 1to 5 carbon atoms for augmenting or enhancing hazelnut, walnut andvanilla flavors.

However, nothing in the prior art suggests the synergistic effect ofmixtures of 3-acetyl-2,5-dialkyl furans or thiophenes and3,5-di-(2-methylpropyl)-1,2,4-trithiolanes particularly for use inaugmenting or enhancing the flavor or aroma of a foodstuff.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an illustration of the apparatus used in which the3,5-di-(2-methylpropyl)-1,2,4-trithiolane of our invention issynthesized according to Example I.

FIG. 2 is the NMR spectrum for fraction 5 of the3,5-di-(2-methylpropyl)-1,2,4-trithiolane of our invention (mixture ofcis and trans isomers) produced according to Example I.

FIG. 3 is the mass spectrum for fraction 5 of the mixture of cis andtrans isomers of 3,5-di-(2-methylpropyl)-1,2,4-trithiolane producedaccording to Example I.

FIG. 4 is the infrared spectrum for the mixture of cis and trans isomersof 3,5-di-(2-methylpropyl)-1,2,4-trithiolane of fraction 5 producedaccording to Example I.

FIG. 5 is the NMR spectrum for the trans isomer of3,5-di-(2-methylpropyl)-1,2,4-trithiolane produced according to ExampleI.

FIG. 6 is the NMR spectrum for the cis isomer of3,5-di-(2-methylpropyl)-1,2,4-trithiolane produced according to ExampleI.

FIG. 7 is the mass spectrum for the trans isomer of3,5-di-(2-methylpropyl)-1,2,4-trithiolane produced according to ExampleI.

FIG. 8 is the mass spectrum for the cis isomer of3,5-di-(2-methylpropyl)-1,2,4-trithiolane produced according to ExampleI.

FIG. 9 is the infrared spectrum for the trans isomer of3,5-di-(2-methylpropyl)-1,2,4-trithiolane produced according to ExampleI.

FIG. 10 is the infrared spectrum for the "cis" isomer of3,5-di-(2-methylpropyl)-1,2,4-trithiolane produced according to ExampleI.

THE INVENTION

The present invention provides mixtures of3,5-di-(2-methylpropyl)-1,2,4-trithiolane and its cis and trans isomershaving the structures: ##STR24## and one or more 3-acetyl-2,5-dialkylfuran or thiophene compounds having the formula ##STR25## wherein X issulfur or oxygen and R and R₁ is lower alkyl of 1 to 5 carbon atoms foraugmenting or enhancing the organoleptic properties in foodstuffs,particularly hazelnut flavored foodstuffs. Such mixtures give rise tosynergistic effects.

The synthesis of the 3,5-di-(2-methylpropyl)-1,2,4-trithiolane of ourinvention is carried out as taught by either Tjan et al, Tetrahedon,Vol. 28, pages 3489-3500 (1972) or according to Asinger et al, LiebigsAnn. Chem. 627,195 (1959) or according to the reaction scheme: ##STR26##whereby isovaleraldehyde is first reacted with a dialkyl amine to forman enamine. The resulting enamine is reacted with hydrogen sulfide toform a mercaptan which is then oxidized to form a disulfide. Theresulting disulfide is then again reacted with hydrogen sulfide to forma dimercaptan-disulfide which is then cyclized to form the3,5-di-(2-methylpropyl)-1,2,4-trithiolane of our invention. Theresulting 3,5-di-(2-methylpropyl)-1,2,4-trithiolane may be used as isfor its organoleptic properties or the "cis" and "trans" isomers thereofmay be separated by means of, for example, preparative columnchromatography or preparative GLC.

The thus produced 3,5-di-(2-methylpropyl-1,2,4-trithiolane and cis andtrans isomers thereof of our invention have roasted, roasted nut, crispbacon-like and pork rind-like aroma and flavor characteristics makingthe 3,5-di-(2-methylpropyl)-1,2,4-trithiolane suitable for use inflavors which can be described as "roasted almond flavors", "roastedhazelnut flavors", "roasted peanut flavors", "roasted pork" flavors,coffee flavors, caramel flavors and "roasted sesame seed" flavors. Thus,the 3,5-di-(2-methylpropyl)-1,2,4-trithiolane and its cis and transisomer of our invention can be used to alter, vary, fortify, modify,augment, enhance or otherwise improve their organoleptic propertiesincluding flavor and/or aroma of a wide variety of materials which areingested, consumed or otherwise organoleptically sensed.

The 3-acetyl-2,5-dialkyl furans or thiophenes can be prepared accordingto Example I or II at columns 6 and 7 of the U.S. Pat. No. 3,885,051issued on May 20, 1975.

The mixtures of 3-acetyl-2,5-dialkyl furan or thiophene compounds and3,5-di-(2-methylpropyl)-1,2,4-trithiolanes of our invention may beprepared by intimately admixing the 3-acetyl-2,5-dialkyl furan orthiophene compounds and 3,5-di-(2-methylpropyl)-1,2,4-trithiolanes in ablender in proportions of from 0.1 part 3-acetyl-2,5-dialkyl furan orthiophene: 0.9 parts 3,5-di-(2-methylpropyl)-1,2,4-trithiolane up to 0.9parts 3-acetyl-2,5-dialkyl furan or thiophene: 0.1 part3,5-di-(2-methylpropyl)-1,2,4-trithiolane.

The terms "alter and modify" in their various forms will be understoodherein to mean the supplying or imparting a flavor character or note toan otherwise bland relatively tasteless substance, or augmenting anexisting flavor characteristic where the natural flavor is deficient insome regard, or supplementing the existing flavor or aroma impression tomodify the organoleptic character. The materials which are so altered ormodified are generally referred to herein as consumable materials.

The term "enhance" as used herein is intended to mean theintensification of a flavor or aroma characteristic, note or nuancewithout the modification of the quality thereof. Thus "enhancement" of aflavor or aroma means that the enhancement agent does not add anyadditional flavor note or nuance in the concentration utilized (basedupon the weight of foodstuff in which it is utilized).

The mixtures of 3-acetyl-2,5-dialkyl furans or thiophenes and3,5-di-(2-methylpropyl)-1,2,4-trithiolanes of this invention areaccordingly useful in flavoring compositions. Flavoring compositions areherein taken to mean those which contribute a part of the overall flavorimpression by supplementing or fortifying a natural or artificial flavorin a material, as well as those which supply substantially all theflavor and/or aroma to a consumable article.

The term "foodstuff" as used herein includes both solid and liquidingestible materials for man or animals, which materials usually do, butneed not, have nutritional value. Thus, foodstuffs includes meats,gravies, soups and convenience food, vegetables, snack foods, dog andcat foods, other veterinary products, and the like.

When the mixtures of 3,5-di-(2-methylpropyl)-1,2,4-trithiolane or its"cis" or "trans" isomers taken together with 3-acetyl-2,5-dialkyl furansor thiophenes according to this invention are used in a food flavoringcomposition, they can be combined with conventional flavoring materialsor adjuvants. Such co-ingredients or flavoring adjuvants are well knownin the art for such use and have been extensively described in theliterature. SUch adjuvant material is required (1) to be substantiallynon-reactive with the mixtures of3,5-di-(2-methylpropyl)-1,2,4-trithiolane or its "cis" or "trans"isomers taken together with 3-acetyl-2,5-dialkyl furans or thiophenesused in our invention particularly whereby unwanted detrimentalorganoleptic properties are not created in the overall organolepticimpression of the ultimate foodstuff used; (2) to be, taken alone ortaken together with other materials used in conjunction therewith,ingestibly acceptable from an aesthetic standpoint and from anorganoleptic standpoint; (3) to be non-toxic and (4) to be otherwisenon-deleterious. Apart from these requirements, conventional materialscan be used and broadly include other flavor materials, vehicles,stabilizers, thickeners, surface active agents, conditioners, and flavorintensifiers.

Examples of preferred co-flavoring adjuvants are:

Methyl thiazole alcohol (4-methyl-5-beta-hydroxyethyl thiazole);

2-Methyl butanetiol;

4-Mercapto-2-butanone;

3-Mercapto-2-pentanone;

1-Mercapto-2-propanone;

Benzaldehyde;

Furfural;

Furfuryl alcohol;

2-Mercapto propionic acid;

2-Methylfuran-3-thiol;

2-Methyldihydrofuran-3-thiol;

2-Methyltetrahydrofuran-3-thiol;

2-Ethylfuran-3-thiol;

2-Ethyldihydrofuran-3-thiol;

2-Ethyltetrahydrofuran-3-thiol;

2-Propylfuran-3-thiol;

2-Isopropylfuran-3-thiol;

2-Isopropyldihydrofuran-3-thiol;

2-Isopropyltetrahydrofuran-3-thiol;

2-Propyldihydrofuran-3-thiol;

2,5-Dimethylfuran-3-thiol;

2,5-Dimethyldihydrofuran-3-thiol;

2,5-Dimethyltetrahydrofuran-3-thiol;

2,5-Diethylfuran-3-thiol;

2,5-Diethyldihydrofuran-3-thiol;

2,5-Diethyltetrahydrofuran-3-thiol;

2-Ethyl-5-methylfuran-3-thiol;

2-Methyl-5-ethylfuran-3-thiol;

2-Ethyl-5-methyldihydrofuran-3-thiol;

2-Ethyl-5-methyltetrahydrofuran-3-thiol;

2,5-Dipropylfuran-3-thiol;

2,5-Diisopropylfuran-3-thiol;

5-Isopropyl-2-methylfuran-3-thiol;

2-Butylfuran-3-thiol;

2-Ethyl-5-propyltetrahydrofuran-3-thiol;

Bis(2-methyl-3-furyl)sulfide;

Bis(2-methyl-3-furyl)disulfide;

Bis(2-ethyl-3-furyl)sulfide;

Bis(2-ethyl-3-furyl)disulfide;

Bis(2,5-dimethyl-3-furyl)sulfide;

Bis(2,5-dimethyl-3-furyl)disulfide;

Bis(2-methyl-3-dihydrofuryl)sulfide;

Bis(2-methyl-3-tetrahydrofuryl)sulfide;

Bis(2-methyl-3-tetrahydrofuryl)disulfide;

Bis(2-methyl-3-dihydrofuryl)disulfide;

Bis(2,5-diethyl-3-furyl)sulfide;

Bis(2-ethyl-5-methyl-3-furyl)disulfide;

Bis(2,5-diethyl-3-furyl)disulfide;

Bis(2,5-dipropyl-3-furyl)disulfide;

Bis(2,5-dipropyl-3-furyl)sulfide;

Bis(2,5-dibutyl-3-furyl)disulfide;

Bis(5-ethyl-2-methyl-3-dihydrofuryl)disulfide

Bis(2-isopropyl-3-furyl)sulfide;

Bis(2-isopropyl-3-furyl)disulfide;

Bis(2-isopropyl-3-dihydrofuryl)sulfide;

Bis(2-isopropyl-3-tetrahydrofuryl)disulfide;

Alkyl pyrazine;

Methyl pyrazine;

2-Ethyl-3-methyl pyrazine;

Tetramethyl pyrazine;

Dipropyl disulfide;

Methyl venzyl disulfide;

Alkyl thiophenes;

2-Butyl thiophene;

2,3-Dimethyl thiophene;

5-Methyl furfural;

Acetyl furan;

2,4-Decadienal;

Guiacol;

Phenol acetaldehyde;

ω-Decalactone;

ω-Limonene;

Acetoin;

Amyl acetate;

Maltol;

Ethyl butyrate;

Levulinic acid;

Piperonal;

Ethyl acetate;

n-Octanal;

n-Pentanal;

Hexanal;

Diacetyl;

Monosodium glutamate;

Sulfur-containing amino acids;

Cysteine;

Hydrolyzed vegetable protein;

Hydrolyzed fish protein;

Tetramethyl pyrazine;

3-acetyl-2,5-dimethylfuran; and

3-acetyl-2,5-dimethylthiophene.

The mixtures of 3,5-di-(2-methylpropyl)-1,2,4-trithiolane or its "cis"or "trans" isomers taken together with 3-acetyl-2,5-dialkyl furans orthiophenes or the compositions incorporating them, as mentioned above,can be combined with one or more vehicles or carriers for adding them tothe particular product. Vehicles can be edible or otherwise suitablematerials such as ethyl alcohol, propylene glycol, water and the like.Carriers include materials such as gum arabic, carrageenan, other gumsand the like. The mixtures of 3,5-di-(2-methylpropyl)-1,2,4-trithiolaneor its "cis" or "trans" isomers taken together with 3-acetyl-2,5-dialkylfurans or thiophenes according to this invention can be incorporatedwith the carriers by conventional means such as spray-drying,drum-drying, and the like. Such carriers can also include materials forcoacervating the mixtures of 3,5-di-(2-methylpropyl)-1,2,4-trithiolaneor its "cis" or "trans" isomers taken together with 3-acetyl-2,5-dialkylfurans or thiophenes (and other flavoring ingredients, as present) toprovide encapsulated products. When the carrier is an emulsion theflavoring composition can also contain emulsifiers such as mono- anddiglycerides of fatty acids and the like. With these carriers orvehicles, the desired physical form of the composition can be prepared.

The quantity of the mixtures of3,5-di-(2-methylpropyl)-1,2,4-trithiolane or its "cis" or "trans"isomers taken together with 3-acetyl-2,5-dialkyl furans or thiophenesshould be sufficient to impart the desired flavor characteristic to theproduct, but on the other hand, the use of an excessive amount of thederivative is not only wasteful and uneconomical, but in some instancestoo large a quantity may unbalance the flavor or other organolepticproperties of the product consumed. The quantity used will varydepending upon the ultimate foodstuff; the amount and type of flavorinitially present in the foodstuff; the further process or treatmentsteps to which the foodstuff will be subjected; regional and otherpreference factors; the type of storage, if any, to which the productwill be subjected; and the preconsumption treatment, such as baking,frying, and so on, given to the product by the ultimate consumer.Accordingly, the terminology "effective amount" and "sufficient amount"is understood in the context of the present invention to bequantitatively adequate to alter the flavor of the foodstuff.

It is accordingly preferred that the ultimate compositions contain fromabout 0.0005 parts per million (ppm) to about 250 ppm of mixtures of3,5-di-(2-methylpropyl)-1,2,4-trithiolane or its "cis" or "trans"isomers taken together with 3-acetyl-2,5-dialkyl furans or thiophenes.More particularly, in food compositions, it is desirable to use fromabout 0.005 ppm to 100 ppm to enhancing flavors and in certain preferredembodiments of the invention, from about 0.2 to 50 ppm of thederivatives are included to add positive flavors to the finishedproduct. All parts, proportions, percentages, and ratios herein are byweight unless otherwise indicated.

The amount of the mixtures of 3,5-di-(2-methylpropyl)-1,2,4-trithiolaneor its "cis" or "trans" isomers taken together with 3-acetyl-2,5-dialkylfurans or thiophenes of our invention to be utilized in flavoringcompositions can be varied over a wide range to the foodstuff. Thus,amounts of one or more derivatives according to the present invention offrom about 2 ppm up to 80 or 90 percent of the total flavoringcomposition can be incorporated in such compositions. It is generallyfound to be desirable to include from about 10 ppm up to about 20percent of the mixture of 3,5-di-(2-methylpropyl)-1,2,4-trithiolane orits "cis" or "trans" isomers taken together with 3-acetyl-2,5-dialkylfurans or thiophenes in such compositions.

The following examples are given to illustrate embodiments of theinvention as it is preferably preferred to practice it. It will beunderstood that these examples are illustrative and the invention is notto be considered as restricted thereto except as indicated in theappended claims.

EXAMPLE I PREPARATION OF 3,5-DI-(2-METHYLPROPYL)-1,2,4-TRITHIOLANE ANDITS CIS AND TRANS ISOMERS

Reaction: ##STR27##

Using the apparatus illustrated in FIG. 1, into a 1 liter 3-necked flask(1, fitted with a thermometer (15) stirrer (14) and addition funnel (13)and an isopropyl alcohol/dry-ice condenser (16) is placed diisopropylenamine (1 mole, lol grams) over a period of 20 minutes, dropwise. Thediisopropyl amine is cooled by means of an ice/salt mixture at 5° C.with stirring. The diisopropyl amine is stirred for a period of 30minutes. Isovaleric aldehyde (1 mole, 86 grams) is added dropwise fromthe dropping funnel (13) at such a rate that the temperature remains at0°-5° C. The addition of the isovaleraldehyde takes place over a periodof 30 minutes. The mixture is then stirred vigorously for about 2 hours.Hydrogen sulfide is then doubled in to the reaction flask (1) fromcylinder (10) until saturation. Any hydrogen sulfide which evolvesunreacted from reaction flask (1) is trapped in the Primol® trap(Primol® is a registered trademark of the Exxon Corporation of Linden,New Jersey for identifying a hydrocarbon edible mineral oil), and (11a);and empty traps (12, 12a, 12b and 12c); and 40 % sodium hydroxideaqueous liquid containing traps (17 and 17a) and a chlorox trap(containing a solution of sodium hypochloride) (18).

Sulfur (0.5 moles, 16 grams) is then added to the reaction mass in smallportions while stirring for a period of one hour and maintaining thereaction temperature at 0°-5° C. The resulting mixture is then allowedto come to room temperature and stirred for a period of four hours. Theresulting organic oil is acidified with 2 molar acetic acid and thenextracted with diethyl ether. The ether extract is washed with water anddried over anhydrous magnesium sulfate. The dried ether extract is thenevaporated on a rotary evaporator yielding a crude material weighing 106grams. 60% of this crude material is the product3,5-di-(2-methylpropyl)-1,2,4-trithiolane having the structure:##STR28## Accordingly, the yield equals 36%. The crude material isdistilled on a micro distillation column after adding thereto 10 gramsof Primol® yielding the following fractions:

    ______________________________________                                              Vapor    Liquid    Vac.                                                 No.   Temp.    Temp.     mmHg   Wt. g. purity %                               ______________________________________                                        1      64-100  114-124   0.45                                                 2     102      127       0.45                                                 3     102      129       0.45   3.0    96.2%                                  4     102      133       0.45   6.6    98.0                                   5     102      137       0.45   3.8    98.0                                   6     106      148       0.45   6.7    94.5                                   7     113      171       0.45   83                                            8     120      175       0.45   11.2                                          9     130      184       0.45   19.0                                          ______________________________________                                    

The fraction 5 of the distillate then separated into two isomers using aCarbowax 20 M GLC column, a cis isomer and a trans isomer.

FIG. 2 is the NMR spectrum for fraction 5. FIG. 3 is the mass spectrumfor fraction 5. FIG. 4 is the infrared spectrum for fraction 5. Fraction5 contains a mixture of "cis" and "trans" isomers of3,5-di-(2-methylpropyl)-1,2,4-trithiolane having the structure:##STR29##

FIG. 5 is the NMR spectrum for the "trans" isomer of3,5-di-(2-methylpropyl)-1,2,4-trithiolane having the structure:##STR30##

FIG. 6 is the NMR spectrum for the "cis" isomer of3,5-di-(2-methylpropyl)-1,2,4-trithiolane having the structure:##STR31##

FIG. 7 is the mass spectrum for the "trans" isomer of3,5-di-(2-methylpropyl)-1,2,4-trithiolane.

FIG. 8 is the mass spectrum for the "cis" isomer of3,5-di-(2-methylpropyl)-1,2,4-trithiolane.

FIG. 9 is the infrared spectrum for the "trans" isomer of3,5-di-(2-methylpropyl)-1,2,4-trithiolane.

FIG. 10 is the infrared spectrum for the "cis" isomer of3,5-di(2-methylpropyl)-1,2,4-trithiolane.

Fraction 5 is indicated at 1 ppm to have a roasted, crisp bacon-like,pork rind-like aroma and flavor characteristic.

EXAMPLE II

The following ingredients are refluxed for four hours:

    ______________________________________                                        Ingredient         Parts by Weight                                            ______________________________________                                        L-Cysteine hydrochloride                                                                         0.9                                                        Carbohydrate-free vegetable                                                   protein hydrolysate                                                                              30.9                                                       Thiamine hydrochloride                                                                           0.9                                                        Water              67.30                                                      ______________________________________                                    

The resulting mixture is then aged for 3 days and an aliquot portion iswithdrawn and dried. Based on the weight of the dry solid obtained,sufficient gum arabic is added to the batch to provide a compositioncontaining one part by weight of gum arabic. The composition is thenspray-dried.

A mixture if "cis" and "trans" isomers of3,5-di(2-methylpropyl)-1,2,4-trithiolane (fraction 5) produced accordingto Example I is added to the spray-dried material to a concentration of3 ppm. The resulting material has an excellent roast pork flavor.

EXAMPLE III

A roast pork flavored gravy is made by formulating a composition in theamounts indicated under ingredient and parts by weight:

    ______________________________________                                        Ingredient         Parts by Weight                                            ______________________________________                                        Cornstarch         10.50                                                      The final product produced                                                    according to Example II                                                                          3.00                                                       Caramel color      .30                                                        Garlic powder      .05                                                        White pepper       .05                                                        Salt               1.92                                                       Monosodium glutamate                                                                             .20                                                        ______________________________________                                    

To one unit of gravy flavor concentrate, eight ounces of water is added,and the mixture is stirred thorougly to disperse the ingredients,brought to a boil, simmered for 1 minute and served. This "meatless"pork flavored gravy exhibits an excellent unique sweet roasted porkflavor.

EXAMPLE IV

3,5-di-(2-methylpropyl)-1,2,4-trithiolane (fraction 5 produced accordingto Example I) is added to beef broth (Wyler's beef broth) prepared froma commercial dried mixture and 250 ml hot water to yield a finalconcentation of 2 ppm of 3,5-di-(2-methylpropyl)-1,2,4-trithiolane. The3,5-di-(2-methylpropyl)-1,2,4-trithiolane increases the sweet meat,smoked and pork rind-like character and enhances the broth-like note.The resultant beef broth has an improved more blended sweet meaty flavorand pork-type flavor than does the unflavored beef broth.

EXAMPLE V

The following ground sausage mixture is prepared:

    ______________________________________                                        Ingredient         Parts by Weight                                            ______________________________________                                        Ground Beef        200                                                        Beef suet          120                                                        Ice/NaCl (50:50 mixture)                                                                         200                                                        Potato flour       100                                                        Anhydrous bread crumbs                                                                           140                                                        Dry milk powder     20                                                        Standard spice flour*                                                                             10                                                        ______________________________________                                        *The standard spice flavor contains:                                          Ingredient       Parts by Weight                                              ______________________________________                                        Oil of cumin     1.5                                                          Oil of mustard   3.5                                                          Oil of celery    3.5                                                          Oil of ginger    5.0                                                          Oil of cloves    14.5                                                         Oil of coriander 18.0                                                         Oil of pimenta berries                                                                         22.0                                                         Oil of black pepper                                                                            45.0                                                         Oleoresin capsicum                                                                             375.0                                                        Oil of nutmeg    500.0                                                        ______________________________________                                    

To the above mixture 0.02% by weight of the following mixture is added:

    ______________________________________                                        Ingredient          Parts by Weight                                           ______________________________________                                        3,5-di(2-methylpropyl)-1,2,4-                                                 trithiolane (prepared according                                               to Example I, fraction 5)                                                                          5                                                        Ethyl alcohol       95                                                        ______________________________________                                    

The resulting mixture is then formed into a sausage and encased in theusual manner. The encased sausage is heated in water at a temperature of160°-180° F. for a period of 2 hours. This sausage has a sweetpork-taste with crisp bacon nuances reminiscent of the taste of sausagemade with natural pork.

EXAMPLE VI

The following mixture is prepared:

    ______________________________________                                        Formula A                                                                     Ingredient          Parts by Weight                                           ______________________________________                                        ethyl maltol        1                                                         maltol              2                                                         vanillin            4                                                         methyl cyclopentenolone                                                                           5                                                         benzaldehyde        1                                                         resorcin dimethyl ether 0.1%                                                  (in 95% ethyl alcohol)                                                                            1                                                         absolute Fenugreek 1%                                                         (in 95% ethyl alcohol)                                                                            5                                                         ethyl oleate        1                                                         gamma-nonalactone 1%                                                          (in 95% ethyl alcohol)                                                                            5                                                         trimethyl pyrazine 0.1%                                                       (in 95% ethyl alcohol)                                                                            2                                                         2-ethyl-5-methyl pyrazine 0.1%                                                (in 95% ethyl alcohol)                                                                            1                                                         alcohol 95%         12                                                        propylene glycol    60                                                        ______________________________________                                    

To Formulation A, 0.1 part of 3,5-di-(2-methylpropyl)-1,2,4-trithiolane(prepared according to Example I, fraction 5) is added and the resultingmixture is evaluated by a bench panel of four members. The conclusion ofthe bench panel is that the 3,5-di-(2-methylpropyl)-1,2,4-trithiolanecontributes a roasted nuance to this hazelnut-like formulation andcauses it to be more natural-like.

To Formula A with 0.01 part of3,5-di-(2-methylpropyl)-1,2,4-trithiolane, 0.1 part of3-acetyl-2,5-dimethylfuran is also added and resulting mixture isevaluated by a bench panel of four members. The conclusion of the benchpanel is that the mixture of 3-acetyl-2,5-dimethylfuran and3,5-di-(2-methylpropyl)-1,2,4-trithiolane (in a 5:50 ratio,weight:weight) gives rise to an interesting roasted hazelnut flavor withsweet, dried nuances. It is the opinion of the bench panel in additionthat the combination of 3-acetyl-2,5-dimethylfuran and3,5-di-(2-methylropyl)1,2,4-trithiolane is a synergistic combinationgiving rise to organoleptic properties over and above the sum total ofthe two individual compounds.

EXAMPLE VII

The following mixture is prepared:

    ______________________________________                                        Ingredients          Parts by Weight                                          ______________________________________                                        Ethyl Maltol         1                                                        Maltol               2                                                        Vanillin             4                                                        Methyl Cyclopentenolone                                                                            5                                                        Benzaldehyde         1                                                        Resorcin Dimethyl Ether 0.1%                                                  (in 95% ethyl alcohol)                                                                             1                                                        Absolute Fenugreek 1%                                                         (in 95% ethyl alcohol)                                                                             5                                                        Ethyl Oleate         1                                                        Gamma-Nonalactone 1%                                                          (in 95% ethyl alcohol)                                                                             5                                                        Trimethyl Pyrazine 0.1%                                                       (in 95% ethyl alcohol)                                                                             2                                                        2-Ethyl-5-Methyl Pyrazine 0.1%                                                (in 95% ethyl alcohol)                                                                             1                                                        Alcohol 95%          12                                                       Propylene Glycol     60                                                       ______________________________________                                    

The formulation is admixed with the material to be tested and theresulting admixture is diluted in water at the rate of 100 ppm. Thewater solutions are compared at equal intensity levels. Each of the testsolutions is tasted and smelled. This is a subjective test but anaccepted procedure for evaluating the relative suitability of candidatecompounds and mixtures as ingredients in foodstuffs if the test iscarried out by a professional flavorist or flavor chemist.

The investigations described above comparing the taste and aroma ofsolutions of equal intensity of test compounds and mixture give rise tothe following results:

A. The Basic Flavor Formulation supra is compared with and without theaddition of 0.1% 3,5-di-(2-methylpropyl)-1,2,4-trithiolane at the rateof 100 ppm in water. The flavor with the3,5-di-(2-methylpropyl)-1,2,4-trithiolane has additional roasted,roasted hazelnut notes missing in the flavor without the3,5-di-(2-methylpropyl)-1,2,4-trithiolane. Therefore, the flavor withthe 3,5-di-(2-methylpropyl)-1,2,4-trithiolane is preferred by all panelmembers when tested by a bench panel.

B. The Basic Formulation, supra, is compared with and without theaddition of 0.1% 2,5-dimethyl-3-acetylfuran at the rate of 100 ppm inwater. The flavor with the 2,5-dimethyl-3-acetylfuran has sweet,dried/light roasted hazelnut and notes as found in haxelnut paste.Therefore, the flavor with the 2,5-dimethyl-3-acetylfuran has beenpreferred by all panel members when tested by a bench panel of fivemembers.

C. The Basic Formulation, supra, is compared with the addition of 0.1%3,5-di-(2-methylpropyl)-1,2,4-trithiolane and 0.1% of3-acetyl-2,5-dimethylfuran against the flavor formulations as in "A" and"B" at 100 ppm in water. The taste is over-roasted and nearlybacon-roasted like. Therefore, the bench panel concluded that there is asynergistic effect resulting from the use of3,5-di-(2-methylpropyl)-1,2,4-trithiolane.

D. The Basic Formulation, supra, has been compared with the addition of0.01% 3,5-di-(2-methylpropyl)-1,2,4-trithiolane and 0.1% of2,5-dimethyl-3-acetylfuran at the rate of 100 rpm. The taste of thiscombination is better than the flavors of "A, B, or C"; pleasant,roasted hazelnut character with good dried, sweet, hazelnut notes. It isobvious that the material, 3,5-di-(2-methylpropyl)-1,2,4-trithiolanehas, together with the compound 2,5-dimethyl-3-acetylfuran, asynergistic effect on the roasted notes. All panel members preferred thecombination of "D" over all other combinations or the basicformulations.

The foregoing results give rise to the conclusion that the combinationeither in a 1:1 ratio or in 1:0.1 ratio of2,5-dimethyl-3-acetylfuran:3,5-di-(2-methylpropyl)-1,2,4-trithiolane hasorganoleptic effects insofar as augmenting or enhancing foodstuffflavors which effect is considered to be "synergistic" when compared tothe organoleptic properties of the individual materials of the mixture:

(i) 3,5-di-(2-methylpropyl)-1,2,4-trithiolane; and

(ii) 2,5-dimethyl-3-acetylfuran

and this organoleptic effect which is synergistic is unexpected,unobvious and advantageous given the properties of the individualcompounds of the combination, namely, 2,5-dimethyl-3-acetylfuran and3,5-di-(2-methylpropyl)-1,2,4-trithiolane.

What is claimed is:
 1. A process for augmenting or enhancing thehazelnut flavor of a hazelnut flavored foodstuff comprising the step ofadding to a hazelnut flavored foodstuff from about 0.0005 ppm up toabout 250 ppm of a composition of matter consisting essentially of2,5-dimethyl-3-acetylfuran and3,5-di-(2-methylpropyl)-1,2,4-trithiolane, the ratio of said2,5-dimethyl-3-acetylfuran: 3,5-di-(2-methylpropyl)-1,2,4-trithiolanebeing from 1:1 to 1:0.1.